1. Field of the Invention
This invention relates to bag filter apparatus that is adapted to receive gas carrying a quantity of dust or other particulate matter whereby the dust is retained by the filter apparatus and only dust-free gas is permitted to pass therethrough. A complete apparatus usually comprises an assembly having a plurality of gas pervious filter bags that are supported by an apertured tube sheet and mounted directly on the outer surface of a cylindrical wire frame or "cage" of transverse circular bands and longitudinal rods welded thereto at their points of contact. Inasmuch as a complete bag filter assembly may incorporate a total of from 100 to 200 filter bags with each one having an average length of from 10 to 15 feet, it is readily apparent that the total volume of all assembled units of a bag filter is large and it incorporates many units having a high volume/weight ratio whose shipping and storage costs are excessive. Moreover, the welding of all bag supports is a time-consuming, expensive project that contributes to excessive manufacturing, shipping, storing and assembling costs.
2. Description of the Prior Art
Various patents have been granted to the particular manner of supporting a cylindrical support frame or cage for a tubular shaped bag filter. Representative of these patents is U.S. Pat. No. 3,538,687 of Pausch granted on Nov. 10, 1970, in which a spiral support member is bonded to a series of longitudinal rods as by "welding" to provide a stable bag support. A similar U.S. Pat. No. 3,016,984 granted Jan. 16, 1962, shows a skeletal inner housing member of transverse rings and longitudinal rods bonded thereto to form a cage over which a filter bag is stretched to provide a filter bag assembly of given configuration.
In all instances known, the skeletal support or cage comprises a plurality of lateral rings or supports having a number of longitudinal stringers connected thereto at their points of contact.